<?php
/**
 * XOOPS Criteria parser for database query
 *
 * You may not change or alter any portion of this comment or credits
 * of supporting developers from this source code or any supporting source code 
 * which is considered copyrighted (c) material of the original comment or credit authors.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * @copyright       The XOOPS Project http://sourceforge.net/projects/xoops/
 * @license         http://www.fsf.org/copyleft/gpl.html GNU public license
 * @package         kernel
 * @subpackage      database
 * @since           2.0.0
 * @author          Kazumi Ono <onokazu@xoops.org>
 * @author          Nathan Dial
 * @author          Taiwen Jiang <phppp@users.sourceforge.net>
 * @version         $Id: criteria.php 2071 2008-09-12 07:12:34Z phppp $
 */

/**
 * 
 * 
 * @package     kernel
 * @subpackage  database
 * 
 * @author	    Kazumi Ono	<onokazu@xoops.org>
 * @copyright	copyright (c) 2000-2003 XOOPS.org
 */

/**
 * A criteria (grammar?) for a database query.
 * 
 * Abstract base class should never be instantiated directly.
 * 
 * @abstract
 * 
 * @package     kernel
 * @subpackage  database
 * 
 * @author	    Kazumi Ono	<onokazu@xoops.org>
 * @copyright	copyright (c) 2000-2003 XOOPS.org
 */
class CriteriaElement
{
    /**
	 * Sort order
     * @var	string
	 */
    var $order = 'ASC';

    /**
     * @var	string
     */
    var $sort = '';

    /**
     * Number of records to retrieve
     * @var	int
     */
    var $limit = 0;

    /**
     * Offset of first record
     * @var	int
     */
    var $start = 0;

    /**
     * @var	string
     */
    var $groupby = '';

    /**
     * Constructor
     **/
    function CriteriaElement()
    {

    }

    /**
     * Render the criteria element
     */
    function render()
    {

    }

    /**#@+
    * Accessor
    */
    /**
     * @param	string  $sort
     */
    function setSort($sort)
    {
        $this->sort = $sort;
    }

    /**
     * @return	string
     */
    function getSort()
    {
        return $this->sort;
    }

    /**
     * @param	string  $order
     */
    function setOrder($order)
    {
        if ('DESC' == strtoupper($order)) {
            $this->order = 'DESC';
        }
    }

    /**
     * @return	string
     */
    function getOrder()
    {
        return $this->order;
    }

    /**
     * @param	int $limit
     */
    function setLimit($limit = 0)
    {
        $this->limit = intval($limit);
    }

    /**
     * @return	int
     */
    function getLimit()
    {
        return $this->limit;
    }

    /**
     * @param	int $start
     */
    function setStart($start = 0)
    {
        $this->start = intval($start);
    }

    /**
     * @return	int
     */
    function getStart()
    {
        return $this->start;
    }

    /**
     * @param	string  $group
     */
    function setGroupby($group)
    {
        $this->groupby = $group;
    }

    /**
     * @return	string
     */
    function getGroupby()
    {
        return $this->groupby ? " GROUP BY {$this->groupby}" : "";
    }
    /**#@-*/
}

/**
 * Collection of multiple {@link CriteriaElement}s 
 * 
 * @package     kernel
 * @subpackage  database
 * 
 * @author	    Kazumi Ono	<onokazu@xoops.org>
 * @copyright	copyright (c) 2000-2003 XOOPS.org
 */
class CriteriaCompo extends CriteriaElement
{

    /**
     * The elements of the collection
     * @var	array   Array of {@link CriteriaElement} objects
     */
    var $criteriaElements = array();

    /**
     * Conditions
     * @var	array
     */
    var $conditions = array();

    /**
     * Constructor
     * 
     * @param   object  $ele
     * @param   string  $condition
     **/
    function CriteriaCompo($ele = null, $condition = 'AND')
    {
        if (isset($ele)) {
            $this->add($ele, $condition);
        }
    }

    /**
     * Add an element
     * 
     * @param   object  &$criteriaElement
     * @param   string  $condition
     * 
     * @return  object  reference to this collection
     **/
    function &add(&$criteriaElement, $condition = 'AND')
    {
        if (is_object($criteriaElement)) {
            $this->criteriaElements[] =& $criteriaElement;
            $this->conditions[] = $condition;
        }
        return $this;
    }

    /**
     * Make the criteria into a query string
     * 
     * @return	string
     */
    function render()
    {
        $ret = '';
        $count = count($this->criteriaElements);
        if ($count > 0) {
            $render_string = $this->criteriaElements[0]->render();
            for ($i = 1; $i < $count; $i++) {
                if (!$render = $this->criteriaElements[$i]->render()) continue;
                $render_string .= ( empty($render_string) ? "" : ' ' . $this->conditions[$i] . ' ' ) . $render; 
            }
            $ret = empty($render_string) ? '' : "({$render_string})";
        }
        return $ret;
    }

    /**
     * Make the criteria into a SQL "WHERE" clause
     * 
     * @return	string
     */
    function renderWhere()
    {
        $ret = $this->render();
        $ret = ($ret != '') ? 'WHERE ' . $ret : $ret;
        return $ret;
    }

    /**
     * Generate an LDAP filter from criteria
     *
     * @return string
     * @author Nathan Dial ndial@trillion21.com
     */
    function renderLdap()
    {
        $retval = '';
        $count = count($this->criteriaElements);
        if ($count > 0) {
            $retval = $this->criteriaElements[0]->renderLdap();
            for ($i = 1; $i < $count; $i++) {
                $cond = strtoupper($this->conditions[$i]);
                $op = ($cond == "OR") ? "|" : "&";
                $retval = "({$op}{$retval}" . $this->criteriaElements[$i]->renderLdap() . ")";
            }
        }
        return $retval;
    }
}


/**
 * A single criteria
 * 
 * @package     kernel
 * @subpackage  database
 * 
 * @author	    Kazumi Ono	<onokazu@xoops.org>
 * @copyright	copyright (c) 2000-2003 XOOPS.org
 */
class Criteria extends CriteriaElement
{

    /**
     * @var	string
     */
    var $prefix;
    var $function;
    var $column;
    var $operator;
    var $value;

    /**
     * Constructor
     * 
     * @param   string  $column
     * @param   string  $value
     * @param   string  $operator
     **/
    function Criteria($column, $value = '', $operator = '=', $prefix = '', $function = '')
    {
        $this->prefix = $prefix;
        $this->function = $function;
        $this->column = $column;
        $this->value = $value;
        $this->operator = $operator;
    }

    /**
     * Make a sql condition string
     * 
     * @return  string
     **/
    function render()
    {
        $clause = (!empty($this->prefix) ? "{$this->prefix}." : "") . $this->column;
        if ( !empty($this->function) ) {
            $clause = sprintf($this->function, $clause);
        }
		if ( in_array( strtoupper( $this->operator ), array( 'IS NULL', 'IS NOT NULL' ) ) ) {
			$clause .= ' ' . $this->operator;
		} else {
	        if ( '' === ($value = trim($this->value) ) ) {
				return '';
			}
	        if ( !in_array( strtoupper($this->operator), array('IN', 'NOT IN') ) ) {
	            if ( ( substr( $value, 0, 1 ) != '`' ) && ( substr( $value, -1 ) != '`' ) ) {
	                $value = "'{$value}'";
	            } elseif ( !preg_match( '/^[a-zA-Z0-9_\.\-`]*$/', $value ) ) {
	            	$value = '``';
				}
	        }
	        $clause .= " {$this->operator} {$value}";
		}
        return $clause;
    }

    /**
     * Generate an LDAP filter from criteria
     *
     * @return string
     * @author Nathan Dial ndial@trillion21.com, improved by Pierre-Eric MENUET pemen@sourceforge.net
     */
    function renderLdap()
    {
        if ($this->operator == '>') {
            $this->operator = '>=';
        }
        if ($this->operator == '<') {
            $this->operator = '<=';
        }

        if ($this->operator == '!=' || $this->operator == '<>') {
            $operator = '=';
            $clause = "(!(" . $this->column . $operator . $this->value . "))";
        } else {
            if ($this->operator == 'IN') {
                $newvalue = str_replace(array('(', ')') , '', $this->value);
                $tab = explode(',', $newvalue);
                foreach ($tab as $uid) {
                    $clause .= "({$this->column}={$uid})";
                }
                $clause = '(|' . $clause . ')';
            }
            else {
                $clause = "(" . $this->column . $this->operator . $this->value . ")";
            }
        }
        return $clause;
    }

    /**
     * Make a SQL "WHERE" clause
     * 
     * @return	string
     */
    function renderWhere()
    {
        $cond = $this->render();
        return empty($cond) ? '' : "WHERE {$cond}";
    }
}
?>
